This invention relates generally to automatic sprinkler systems and more specifically to an improved sprinkler head that may adjusted by the user to direct the flow of water over a ground area to be watered that is irregular in shape. A number of rotary lawn sprinklers are known in the prior art for watering residential and commercial lawn areas, greenbelts, golf courses, and other grass areas of varying size. U.S. Pat. No. 3,268,173 is directed to a conventional pop-up sprinkler head that rotates to water a circular area represented by a fixed radial distance from the sprinkler head. U.S. Pat. No. 1,997,901 to Englehart is directed to a rotary sprinkler having a fixed base supporting a vertical stem around which a water stream expelling nozzle driven by an impact arm is caused to rotate either continuously or back and forth between arcuate stop positions to water either a complete circular area or a circular sector area. The water stream exiting the nozzle of this prior art sprinkler strikes an adjustable deflector plate fixedly attached to the nozzle assembly, thereby allowing the user to set the fixed radius of the full circle or circular sector being watered.
Oftentimes, the area being watered by such sprinklers is irregular in shape so that directing a stream of water over full circle or circular sector areas either results in watering areas not intended to be watered or in missing areas that are in need of water. Both of these situations are undesirable. Several prior art sprinklers provide non-circular watering patterns that may be selected by the user. U.S. Pat. No. 2,999,643 to Kennedy is directed to a rotary sprinkler employing a complex cam arrangement for adjusting the watering pattern of the sprinkler. U.S. Pat. No. 4,984,740 to Hodge is directed to a rotary sprinkler that emits a stream whose distance is adjustable by means of a series of adjustable sliding blocks that controls the position of a flap on which the emitted stream impinges. U.S. Pat. No. 3,528,093 is directed to a rotary sprinkler in which a cam arrangement is provided to permit watering of an area that is square in shape. U.S. Pat. No. 3,272,437 to Coson is directed to a rotary sprinkler in which a cam arrangement is provided to permit watering a delineated circular sector. U.S. Pat. No. 3,952,954 is directed to a rotary sprinkler in which the speed of rotation of the nozzle and the angle of elevation of the water stream emitted by the nozzle are controlled to distribute water over an irregular pattern. U.S. Pat. No. 1,593,918 to Stanton is directed to a rotary sprinkler in which the emitted stream of water may be confined within a square area or one bordered by straight lines. U.S. Pat. No. 4,281,793 to DeWitt is directed to a rotary sprinkler in which a mechanism is provided for altering the volume of water flow to the spray head to thereby define the watering pattern on the ground. U.S. Pat. No. 4,453,673 to Icenbice is directed to a rotary sprinkler in which a cam plate is provided to control the range of the water stream emitted from the sprinkler. U.S. Pat. No. 4,637,549 is directed to a rotary sprinkler in which rotation speed and a splash plate control the distance that the water stream will project from the water nozzle outlet. U.S. Pat. No. 4,538,762 to Lemkin is directed to a rotary sprinkler in which a cam arrangement is provided to permit adjustment of the watering pattern. U.S. Pat. No. 5,031,840 to Grundy et al. is directed to a rotary sprinkler in which dual nozzles, one of which employs radial channels therein, are employed to control the radius of the water stream emitted from the sprinkler. U.S. Pat. No. 4,540,125 is directed to a rotary sprinkler employing a first cam apparatus for controlling a water deflector to thereby select an overall size and pattern of sprinkler stream coverage and a second cam apparatus for determining the desired sprinkling pattern as a function of the azimuthal orientation of the nozzle. The foregoing prior art sprinklers typically involve complex mechanisms that are expensive and do not permit easy adjustment of the stream distance by the user. They are generally not retrofittable to previously installed sprinklers, and some are not adaptable to a pop-up type of rotary sprinkler.
It is therefore the principal object of the present invention to provide a rotary water sprinkler in which a simple mechanical arrangement is employed to permit the user to quickly and easily adjust the distance of the emitted stream of water at various arcuate positions of a full circle or circular sector of rotation of the sprinkler.
This and other incidental objects are accomplished in accordance with the illustrated preferred embodiment of the present invention by providing a deflector cap that may replace the plain cap of a conventional pop-up rotary sprinkler head previously installed or be incorporated into customary pop-up rotary sprinkler heads. The deflector cap is held in a fixed angular position with respect to the sprinkler housing by means of a downwardly extending rod that slides within a tube fixedly attached to the sprinkler housing. An annular array of individually-adjustable, wedge-shaped, flat deflector plates is mounted to the underside of the deflector cap. Each of the deflector plates is formed to have an outer wide end and an inner narrow end. The inner end of each of the deflector plates is hingedly attached to the deflector cap at a uniform radial distance from the center of the deflector cap, thereby permitting vertical movement of the outer ends of each of the deflector plates. The vertical movement is facilitated by a screw adjustment mechanism associated with each of the deflector plates. A thin annular sheet of mylar or other flexible material is attached to the underside of the array of deflector plates adjacent the outer ends thereof to provide a smooth water stream transition as the rotating nozzle of the sprinkler rotationally passes each of the deflector plates. As the nozzle of the sprinkler rotates during operation, the water stream emitted therefrom will be deflected to varying distances by the deflector plates as a function of the angular position of the nozzle in accordance with the vertical adjustment previously made to each of the individual deflector plates.